Help with quadratic functions!!

The bridge opening pictured below is 20 m wide and the road is 10 m from the top of the water. The stones at the vertex of the opening are 0.5 m thick.


If the water level were to raise by 1.5 metres, how wide would the bridge opening be at the level of the water?

Start by assuming that the opening is shaped like a parabola opening downwards.

Introduce a coordinate system; model the initial water surface using the x-axis, and center the parabola so that its vertex is on the y-axis.

The equation will then take the form f(x) = Ax^2 + C.

Now, try to find the coefficients A and C, using the measurements that are given and the notion of symmetry.

Once you have the function defined, you can use it to answer the question.

Please explain your work thus far, if you need to ask additional questions. Cheers :cool: